Premeeting | During the Meeting
- 1. The Serpent Mound Impact Crater and Paleozoic Stratigraphy of Southern Ohio.
Two-day trip; departs Fri., 20 April, 5 p.m.; returns Sat., 21 April, 9 p.m. Cost: US$177. Max.: 22.
Keith A. Milam, Ohio University.
- Participants will observe the undeformed and deformed (target rock) stratigraphy of the Serpent Mound impact crater and will discuss the geologic processes involved in the impact event. Participants will view the crater from along the rim, interior, and central peak. New research concerning the timing and size of the impact event will be discussed and debated as well.
- 2. Lower Silurian of West-Central Ohio and the Case of the Disappearing Dayton.
One-day trip, Sat., 21 April; departs 8 a.m.; returns 5 p.m. Cost: US$81. Max.: 16.
Mark Kleffner, The Ohio State University at Lima; Bradley Cramer, Kansas Geological Survey/University of Kansas; Carlton Brett, University of Cincinnati.
- Participants of this field trip will visit several sites exposing the Lower Silurian of west-central Ohio. Lower Silurian stratigraphy for this region has recently been revised and is comprised of (in ascending order) Brassfield, Dayton, Osgood, Lewisburg, Massie, and Laurel. Although all of these formations vary in thickness within the region, the Dayton is the most variable, ranging in thickness from >3.5 m near its newly designated type locality, John Bryan State Park, to totally absent in a roadcut on the south side of Ohio State Route 571, just west of the Stillwater River, in West Milton. Conodont biostratigraphy and δ13Ccarb chemostratigraphy have recently been developed for each site, resulting in improved correlation of Lower Silurian strata in this region and making possible consideration of the roles eustasy and tectonics likely played in the Early Silurian depositional history at each of the sites to be visited. At each site, an obvious unconformity exists between the Brassfield and overlying formation (Dayton or Osgood). In addition, a site in West Milton on the north side of OSR 571, just east of the Stillwater River, provides an excellent exposure of the Ordovician-Silurian boundary, in which the exact level of that boundary is not inherently obvious, but likely levels can be examined. Other highlights of the field trip include bryozoan bioherms in the Brassfield at one site, nicely preserved casts of brachiopods, trilobites, and nautiloids in the Laurel at another site, and lunch at Young’s Dairy, a landmark in west-central Ohio known for their homemade ice cream.
- 3. Bourbon and Springs in the Bluegrass Region of Kentucky.
One-day trip, Sat., 21 April; departs 6:45 a.m.; returns 6:45 p.m. Cost: US$81. Max.: 22.
Alan Fryar, University of Kentucky; Ashley Barton, University of Kentucky.
- This field trip will explore the role of geology in the origins and production of a distinctly American distilled spirit: Bourbon whiskey originated in the late 1700s and early 1800s in the Bluegrass region of north-central Kentucky. The region is marked by fertile residual soils developed on karstified Lower Paleozoic limestones. Corn was grown, ground, fermented, and distilled to yield a high-value product that would not spoil. The chemistry of “limestone water” (dilute calcium-bicarbonate type with near-neutral pH) limits dissolved iron and promotes the growth of bacteria involved in fermentation. Many farms and settlements were located near perennial springs, whose relatively cool temperatures (~14 to 15 °C) facilitated condensation of steam during distillation. We will visit Royal Spring in Georgetown (an early site of bourbon production, and one of the few springs in Kentucky still used for municipal water supply); McConnell Springs (the site of the original settlement of Lexington and a karst window in which a grist mill once operated); and two distilleries, Woodford Reserve (the oldest and smallest in the state) and Four Roses (located on the National Register of Historic Places).
- 4. Introduction to the Geology of the Dayton Area.
One-day trip, Sat., 21 April; departs 9 a.m.; returns 5 p.m. Cost: US$66. Max.: 20.
- 5. Upper Ordovician Strata of Southern Ohio-Indiana: Shales, Shell Beds, Storms, Sediment Starvation, and Cycles.
One-day trip, Sun., 22 April; departs 9 a.m.; returns 8 p.m. (includes evening meal). Cost: US$83. Max.: 27.
Benjamin Datillo, Indiana University–Purdue University Fort Wayne; Carlton Brett, University of Cincinnati; Thomas Schramm, Louisiana State University.
- The Cincinnatian Series (ca. 450 to 442 Ma) of the Cincinnati Arch features some of the most spectacular Ordovician fossils in the world. The rich faunas of bryozoans, brachiopods, molluscs, echinoderms, and trilobites are preserved as discrete shell-rich limestones, cyclically interbedded with sparsely fossiliferous shales and mudstones that may yield exceptionally preserved trilobites and crinoids. Similar successions of shell beds interbedded with mudstones are common components of Paleozoic successions. In such successions, the genesis of the highly concentrated shell beds is often attributed to storm-winnowing, but is this the whole story? This trip will offer an overview of the classic Cincinnatian Series, with ample opportunity for examining and collecting the rich fossil assemblages throughout much of the succession. Discussions will focus on the origin of interbedded mudstone-limestone cycles. We will emphasize depositional processes, particularly the role of intermittent siliciclastic sediment supply, carbonate (shell) production, and winnowing by storms and other high-energy events in a critical discussion of the storm-winnowing model.
- 6. Scales of Stream Study in West-Central Ohio.
One-day trip, Sun., 22 April; departs 8 a.m.; returns 5 p.m. Cost: US$76. Max.: 18.
John Ritter, Wittenberg University.
- The field trip is basically a fluvial geomorphology and hydrology trip, examining the Little Miami River, a state and national scenic river, and Buck Creek, a heavily impacted, urban river, and its tributaries. Stops will be designed to expose participants to different temporal and spatial scales of study in river systems. The evolution of the Little Miami River and Clifton Gorge, during or following glaciation, would focus on regional streams on geologic time scales. Tributaries of Buck Creek would represent more recent Anthropocene stream change, European settlement to present, with a look at how similar vertical changes have been in second- to fourth-order streams. Finally, we will examine stream recreational changes on Buck Creek (lowhead dams modified for recreation) that have enhanced the overall stream quality in one case, degraded it in another—this part of the trip will focus on instrumentation and field work to assess urban and agricultural impacts and changes over the course of years to hours.
- 7. Dayton Region Geology in Core and Outcrop—A Field Guide for Citizens, Environmental Investigators, Geologists, and Educators.
One-day trip (morning workshop and afternoon field trip), Sun., 22 April; begins 9 a.m.; returns 5 p.m. Cost: US$71. Max.: 22.
Gregory A. Schumacher, Michael P. Angle, Douglas J. Aden, Ohio Department of Natural Resources, Division of Geological Survey; Brian E. Mott, DLZ, Ohio Inc.
- The Ohio Dept. of Natural Resources (ODNR) Division of the Geological Survey, in cooperation with DLZ-Ohio Inc., will host a morning workshop (9 a.m. to noon) and afternoon field trip (1 to 5 p.m.) dedicated to unraveling the mysteries of the near-surface geology of the Dayton, Ohio, region. Participants will learn about diagnostic environmental and geologic characteristics, hydrogeologic properties, general engineering characteristics, potential environmental and geologic hazards, and economic uses for bedrock and Quaternary geologic units in the Dayton region. Attendees also will receive an overview of southwestern Ohio’s near-surface geology and how to use Division of Geological Survey mapping products and will have an opportunity to use fact sheets written for forthcoming publication titled Ohio’s Geology in Core and Outcrop—A Field Guide for Citizens and Environmental and Geotechnical Investigators. Hands-on exercises will bring the Dayton region’s near-surface geologic units alive as participants compare concise fact-sheet descriptions with outcrop photographs and hand and core samples for each unit. After a catered lunch, participants will have the opportunity to examine the Dayton region’s near-surface geologic units in outcrop exposures in order to compare and contrast the same rocks examined during the morning workshop. At each outcrop, participants will have hands-on opportunities to test their descriptive and interpretative skills, to use the field guide fact sheets, and to learn about the diverse geologic relationships of the Dayton region’s near-surface geologic units.
- 8. The First Fossil-Vertebrate Locality in North America—“Big Bone Lick,” Kentucky.
One-day trip, Sun., 22 April; departs 8 a.m.; returns 6 p.m. Cost: US$ 134. Max.: 20.
Richard Arnold Davis, College of Mount St. Joseph; Stanley Hedeen, Xavier University; H. Gregory McDonald, National Park Service; Kenneth B. Tankersley, University of Cincinnati.
- In 1739, a French army, en route from Canada to Louisiana, stopped at a boggy area in what is now northern Kentucky. The ground was littered with big bones and teeth, some of which were gathered up and, in due course, transported to Paris to become the first vertebrate fossils from the New World to be studied scientifically in the Old. With the advent of the United States, the boggy area repeatedly was the site of avid collecting, including by William Henry Harrison, by Meriwether Lewis on his way west to Lewis-and-Clark fame, and, after that expedition, by the other member of the pair, William Clark, on the specific orders of (and paid for by) Thomas Jefferson. Charles Lyell even visited the site in the 1840s. Bones and teeth from “Big Bone” were studied by leading experts on vertebrates of their respective times and countries, including Buffon, Cuvier, Harlan, Leidy, Wistar, and Jefferson himself. Indeed, a number of well-known taxa of Pleistocene animals are based on fossils from “Big Bone,” including Bison antiquus; the “ground-sloth” Paramylodon harlani; the “elk-moose” Cervalces scotti; and the “musk ox” Bootherium bombifrons. Moreover, when Cuvier recognized what we now call “the American Mastodon,” he had at his disposal the very specimens collected by the French army. This field trip will allow participants to visit this historically important paleontological site and experience its geology, paleontology, and archaeology. It is intended not only for individuals whose research is in the Pleistocene per se, but also for those with an interest in the early history of paleontology in the United States and beyond.
- 9. Fossil collecting from the Middle Devonian Silica Shale, West-Central Ohio.
One-day trip, Sun., 22 April; departs 9 a.m.; returns 5 p.m. Cost: US$90. Max.: 20.
Dave Mielke, Botkins, Ohio; Alex Fabian, Michigan; Michael R. Sandy, University of Dayton.
- Field-trip participants will visit a working limestone quarry near Paulding, Ohio, USA, ~100 miles north of Dayton. The quarry is working Middle Devonian strata: the Dundee Formation and overlying Tenmile Creek Dolomite and Silica Formation of the Traverse Group. Of particular interest for this field trip is the Silica Formation (Silica Shale). The experts in the paleontology of the quarry are Dave Mielke and Alex Fabian; both have been collecting from the quarry since the 1990s and have amassed large paleontological collections from the quarry. At Paulding, the thickness of the Silica Formation is much reduced compared to farther north in the vicinity of Sylvania, Ohio. However, it should be possible to make a good collection from the accessible units during the visit, which will be timed with a recent blasting of the rock face. Collecting will be made from and among recently blasted blocks of rock mostly of the Dundee and Silica Formations; be aware that such terrain is uneven. Access to the quarry is courtesy of plant operators LaFarge.
During the Meeting
- 10. Downtown Dayton Walking Tour: Building Stones, Geology, and Commemorating 99 years since The Dayton Flood of 1913.
Two-hour walking tour, Tues., 24 April; departs 2 p.m.; returns 4 p.m. Cost: US$17. Max.: 24.
Michael R. Sandy, University of Dayton.
- This walking tour will allow a number of local geological and historical phenomena to be considered. Initially, it will focus on some examples of building stones used in downtown Dayton buildings. In particular, special attention will be paid to the Dayton Limestone—a stone considered in 1870 by then State Geologist Edward Orton as one of Ohio’s finest building stones. The Dayton Formation limestones were used extensively in the Dayton area (and farther afield) during the nineteenth and early twentieth centuries. The Zenith of the Dayton Limestone Industry is characterized by the Old Courthouse (1850), an important Greek-revival architectural-style building that saw the use of Dayton Limestone not only for the exterior of the building but also, unusually, and perhaps with a little too much enthusiasm, for the roof. This building has much local historical significance because both presidents Abraham Lincoln and John F. Kennedy addressed the public from its steps. In addition, we will consider the Dayton Flood of 1913, an event that caused more than 400 deaths along the Great Miami River Valley. We will be able to see flood-prevention modifications to the channel of the Great Miami River in Downtown Dayton. This GSA meeting will be held just after the 99th anniversary of the Dayton Flood as the centennial of the flood approaches in 2013. The Miami Conservancy District oversees the flood-prevention scheme that developed after the 1913 flood and is housed in a building that overlooks the Great Miami River in Downtown Dayton.